Please apply this patch to contrib/dbmirror

In incorperates changes from myself and a number of contributors.

This update to dbmirror provides:

-replication of sequence operations via setval/nextval
-DBMirror.pl support for logging to syslog
-changed the names of the tables to dbmirror_*  (no quotes required)
-Support for writitng SQL statements to files instead of directly to
 a slave database
-More options for DBMirror.pl in the config files.

Steven Singer

contrib/dbmirror/MirrorSetup.sql

+BEGIN;
+
+SET autocommit TO 'on';
 
 CREATE FUNCTION "recordchange" () RETURNS trigger AS
-'/usr/local/pgsql/lib/pending.so', 'recordchange' LANGUAGE 'C';
+'$libdir/pending.so', 'recordchange' LANGUAGE 'C';
+
 
-CREATE TABLE "MirrorHost" (
-"MirrorHostId" serial,
-"HostName" varchar NOT NULL,
-PRIMARY KEY("MirrorHostId")
-);
 
+CREATE TABLE dbmirror_MirrorHost (
+MirrorHostId serial not null,
+SlaveName varchar NOT NULL,
+PRIMARY KEY(MirrorHostId)
+);
 
 
 
 
-CREATE TABLE "Pending" (
-"SeqId" serial,
-"TableName" varchar NOT NULL,
-"Op" character,
-"XID" int4 NOT NULL,
-PRIMARY KEY ("SeqId")
 
+CREATE TABLE dbmirror_Pending (
+SeqId serial,
+TableName Name NOT NULL,
+Op character,
+XID int4 NOT NULL,
+PRIMARY KEY (SeqId)
 );
 
-CREATE INDEX "Pending_XID_Index" ON "Pending" ("XID");
+CREATE INDEX "dbmirror_Pending_XID_Index" ON dbmirror_Pending (XID);
 
-CREATE TABLE "PendingData" (
-"SeqId" int4 NOT NULL,
-"IsKey" bool NOT NULL,
-"Data" varchar,
-PRIMARY KEY ("SeqId", "IsKey") ,
-FOREIGN KEY ("SeqId") REFERENCES "Pending" ("SeqId") ON UPDATE CASCADE  ON DELETE CASCADE
+CREATE TABLE dbmirror_PendingData (
+SeqId int4 NOT NULL,
+IsKey bool NOT NULL,
+Data varchar,
+PRIMARY KEY (SeqId, IsKey) ,
+FOREIGN KEY (SeqId) REFERENCES dbmirror_Pending (SeqId) ON UPDATE CASCADE  ON DELETE CASCADE
 );
 
 
-CREATE TABLE "MirroredTransaction" (
-"XID" int4 NOT NULL,
-"LastSeqId" int4 NOT NULL,
-"MirrorHostId" int4 NOT NULL,
-PRIMARY KEY  ("XID","MirrorHostId"),
-FOREIGN KEY ("MirrorHostId") REFERENCES "MirrorHost" ("MirrorHostId") ON UPDATE CASCADE ON DELETE CASCADE,
-FOREIGN KEY ("LastSeqId") REFERENCES "Pending" ("SeqId")  ON UPDATE
+CREATE TABLE dbmirror_MirroredTransaction (
+XID int4 NOT NULL,
+LastSeqId int4 NOT NULL,
+MirrorHostId int4 NOT NULL,
+PRIMARY KEY  (XID,MirrorHostId),
+FOREIGN KEY (MirrorHostId) REFERENCES dbmirror_MirrorHost (MirrorHostId) ON UPDATE CASCADE ON DELETE CASCADE,
+FOREIGN KEY (LastSeqId) REFERENCES dbmirror_Pending (SeqId)  ON UPDATE
 CASCADE ON DELETE CASCADE
 );
+
+
+UPDATE pg_proc SET proname='nextval_pg' WHERE proname='nextval';
+
+CREATE FUNCTION pg_catalog.nextval(text) RETURNS int8  AS
+'/usr/local/postgresql-7.4/lib/pending.so', 'nextval' LANGUAGE 'C' STRICT;
+
+
+UPDATE pg_proc set proname='setval_pg' WHERE proname='setval';
+
+CREATE FUNCTION pg_catalog.setval(text,int4) RETURNS int8  AS
+'/usr/local/postgresql-7.4/lib/pending.so', 'setval' LANGUAGE 'C' STRICT;
+
+COMMIT;
\ No newline at end of file

contrib/dbmirror/README.dbmirror

@@ -6,7 +6,7 @@ DBMirror is a database mirroring system developed for the PostgreSQL
 database Written and maintained by Steven Singer(ssinger@navtechinc.com)
 
 
-(c) 2001-2002 Navtech Systems Support Inc.
+(c) 2001-2004 Navtech Systems Support Inc.
 ALL RIGHTS RESERVED
 
   Permission to use, copy, modify, and distribute this software and its
@@ -57,7 +57,7 @@ Pending tables.
 Requirments:
 ---------------------------------
 -PostgreSQL-7.4 (Older versions are no longer supported)
--Perl 5.6(Other versions might work)
+-Perl 5.6 or 5.8 (Other versions might work)
 -PgPerl (http://gborg.postgresql.org/project/pgperl/projdisplay.php)
 
 
@@ -81,13 +81,8 @@ PostgreSQL-7.4  Make Instructions:
 
 You should now have a file named pending.so that contains the trigger.
 
-Install this file in /usr/local/pgsql/lib  (or another suitable location).
+Install this file in your Postgresql lib directory (/usr/local/pgsql/lib)
 
-If you choose a different location the MirrorSetup.sql script will need
-to be modified to reflect your new location.   The CREATE FUNCTION command
-in the MirrorSetup.sql script associates the trigger function with the
-pending.so shared library.  Modify the arguments to this command if you
-choose to install the trigger elsewhere.
 
 2) Run MirrorSetup.sql
 
@@ -95,7 +90,8 @@ This file contains SQL commands to setup the Mirroring environment.
 This includes
 
 -Telling PostgreSQL about the "recordchange" trigger function.
--Creating the Pending,PendingData, MirrorHost, MirroredTransaction tables
+-Creating the dbmirror_Pending,dbmirror_PendingData,dbmirror_MirrorHost, 
+dbmirror_MirroredTransaction tables
 
 
 To execute the script use psql as follows 
@@ -114,17 +110,34 @@ DBMirror.pl script.  See slaveDatabase.conf for a sample.
 The master settings refer to the master database(The one that is
 being mirrored).
 
-The slave settings refer to the database that the data is being mirrored to.
-The slaveHost parameter must refer to the machine name of the slave (Either
-a resolvable hostname or an IP address).  The value for slave host
-must match the Hostname field in the MirrorHost table(See step 6).
+The slave settings refer to the database that the data is being
+mirrored to.
 
-The master user must have sufficient permissions to modify the Pending
-tables and to read all of the tables being mirrored.
+The slaveName setting in the configuration file must match the slave
+name specified in the dbmirror_MirrorHost table.
+
+DBMirror.pl can be run in two modes of operation: 
+
+ A) It can connect directly to the slave database.  To do this specify
+ a slave database name and optional host and port along with a username
+ and password.  See slaveDatabase.conf for details.
+
+
+ The master user must have sufficient permissions to modify the Pending
+ tables and to read all of the tables being mirrored.
+
+ The slave user must have enough permissions on the slave database to
+ modify(INSERT,UPDATE,DELETE) any tables on the slave system that are being
+ mirrored. 
+
+ B) The SQL statements that should be executed on the slave can be
+ written to files which can then be executed slave database through
+ psql.  This would be suitable for setups where their is no direct
+ connection between the slave database and the master. A file is
+ generated for each transaction in the directory specified by
+ TransactionFileDirectory. The file name contains the date/time the
+ file was created along with the transaction id.
 
-The slave user must have enough permissions on the slave database to
-modify(INSERT,UPDATE,DELETE) any tables on the slave system that are being
-mirrored. 
 
 4) Add the trigger to tables.
 
@@ -153,7 +166,7 @@ The name of the host in the MirrorHost table must exactly match the
 slaveHost variable for that slave in the configuration file.
 
 For example
-INSERT INTO "MirrorHost" ("HostName") VALUES ('mySlaveMachine.mycompany.com');
+INSERT INTO "MirrorHost" ("SlaveName") VALUES ('backup_system');
 
 
 6)  Start DBMirror.pl
@@ -171,7 +184,8 @@ Any errors are printed to standard out and emailed to the address specified in
 the configuration file. 
 
 DBMirror can be run from the master, the slave, or a third machine as long
-as it is able to access both the master and slave databases.
+as it is able to access both the master and slave databases(not
+required if SQL files are being generated)
 
 7) Periodically run clean_pending.pl 
 clean_pending.pl cleans out any entries from the Pending tables that
@@ -194,11 +208,28 @@ TODO(Current Limitations)
 ----------
 -Support for selective mirroring based on the content of data.
 -Support for BLOB's.
--Support for conflict resolution.
--Batching SQL commands in DBMirror for better performance over WAN's.
+-Support for multi-master mirroring with conflict resolution.
 -Better support for dealing with Schema changes.
 
 
+
+Significant Changes Since 7.4
+----------------
+-Support for mirroring SEQUENCE's
+-Support for unix domain sockets
+-Support for outputting slave SQL statements to a file
+-Changed the names of replication tables are now named
+dbmirror_pending etc..
+
+
+
+Credits
+-----------
+Achilleus Mantzios <achill@matrix.gatewaynet.com>
+
+
+
+
 Steven Singer
 Navtech Systems Support Inc.
 ssinger@navtechinc.com